Schemathesis CLI
The CLI generates API tests from schemas and gives agents reproducible failures in responses and operation sequences.
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- MIT
Extended access
Why this level
- Generated requests can change API data and create load within the chosen schema and credentials.
Install
In your terminal, with SkillFoxx CLI
npx skillfoxx add cli/schemathesisDetects the agents on your machine, shows the access level and pins the version.
Other ways to install
Access and checks
How we reviewExtended accessThe tool runs code or makes network calls and only reads external data.
- Generated requests can change API data and create load within the chosen schema and credentials.
This is third-party code. Review the repository files before installing.
What it does
Schemathesis generates requests from API schemas and checks server behavior. An agent can run a bounded staging test, inspect validation or server failures and use reproduction commands. Operations can be chained using information from responses. OpenAPI, GraphQL and gRPC are supported, with configurable credentials, rates and operation scope. Reports support reproducing failures after fixes and comparing them with known issues.
Who it is for. API testers finding unexpected-input failures and verifying related operations from service schemas.
Good fit when
- API changes need response-schema checks.
- An agent needs a reproducible server-error case.
- Individually valid operations may fail when chained.
- CI should rerun known failures and detect new ones.
Not a fit when
- Testing is limited to production data with no test-data allowance.
- The API owner has not authorized generated requests.
- The schema cannot be aligned with the current service.
Example request
Prepare a bounded Schemathesis run for our staging OpenAPI and show the endpoint, authentication approach and limits before requests.Limitations
The tool sends real requests that can create, change or delete data; use a development or staging environment with disposable records. Coverage depends on the schema and available credentials, so validate both before execution. Many generated examples create load; set request-rate and generation limits. The current package requires Python 3.11 or later, with optional extras needed for some protocols, such as gRPC.
How to disable. Stop the run and remove its CI job. Restore affected staging data separately and protect reports containing requests and responses.
FAQ
What happens when I run the uvx demo?
Schemathesis sends real test requests to the author’s demo API and displays a report. A separate command installs the CLI permanently.
How do I create an offline report?
Use `--report html`.
Can configuration avoid Python code?
Yes. Use `schemathesis.toml`.
Where do test inputs come from?
Generation uses schemas and can learn constraints or values from server responses.
Can I reproduce a failure?
Yes. Reports include reproduction details and commands, with support for replaying past failures.
Discussion
No questions or reviews yet.
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README in short
Users can add custom business-rule checks to the built-in checks. The project also integrates with Python tests.